Microwave ovens for heating foodstuff are widely used in both residential and commercial/industrial contexts. A microwave oven heats food by using microwave radiation generated from a magnetron, many times faster than conventional means, often without the risk of burning the foodstuff. An oven includes controls to enable a user to adjust output levels and cooking time. Cooking time may be determined by reference to an absolute period of time or the sensed temperature of the heated foodstuff, amongst other ways. Typically, a microwave oven also includes displaying functionality for visually indicating to the user the operational status of the microwave oven when in or prior to heating operation.
Once the heating function has been engaged by a user, there is a period during which the foodstuff is irradiated and the user must wait for the period to terminate before extracting his foodstuff. This period can vary greatly in duration; it may last less than a minute or in certain cases up to tens of minutes. Typically, to heat a prepared meal, a few minutes will suffice. The user has to then opt whether to wait idly for the cooking time to expire or to leave the cooking area and return in a pre-determined amount of time. In the latter case, there is often the possibility of not being able to return in time, resulting in cooling of the foodstuff and necessitating a further heating. The problem is even more difficult if the heating period is determined by way of temperature sensing. In this instance, there is no way of knowing in advance how long irradiation will occur.
In the commercial/industrial context where workers are allocated a fixed period within which to eat and an eating area separate from the work area, a queue often occurs for sequential use of a limited number of microwave ovens in the eating area. Leaving the eating area is not an option, except if someone could be found to look after the foodstuff; neither would a worker leave once joining a queue. The only option is to wait in the area of the microwave oven both before and during heating. During this time, there is an unproductive void when hungry and impatient people wait.